Dieting, restraint, and disinhibition predict women's weight change over 6 y

Abstract

Background: Although disinhibited eating is positively associated with higher weight in women, it is not known whether restrained eating and dieting moderate the influence of disinhibited eating on weight change.

Objective: The objective was to investigate over 6 y the interactive effects of restrained and disinhibited eating and self-reported dieting to lose weight as predictors of weight gain in women.

Design: Data were collected from non-Hispanic white women (n = 163) every 2 y. Height and weight were measured in triplicate. Dietary restraint and disinhibition were assessed by using the Eating Inventory. Participants were also asked if they were "currently dieting to lose weight." Multilevel modeling was used to examine change in weight as a function of time-invariant and time-varying predictors, including dietary restraint, dietary disinhibition, and self-reported dieting.

Results: After covariates were adjusted for, growth curve models showed that within-person increases in restraint over time were associated with concurrent decreases in weight and that higher levels of restraint moderated the positive association between dietary disinhibition and weight. Women who reported dieting at study entry were heavier at study entry and gained more weight over time than did nondieters. Finally, a significant interaction between restraint, disinhibition, and dieting showed that restraint moderated the effect of disinhibition on weight differently in nondieters than in dieters.

Conclusions: Increasing levels of dietary restraint may be beneficial in moderating weight by attenuating the positive association between disinhibition and weight in dieting women. An understanding of weight and weight change requires examination of the interactive effects of restraint, disinhibition, and dieting.

FIGURE 1

Moderation effects of restraint on disinhibition and weight at study entry. The effect differed between nondieters and dieters (n = 163). Weight values were predicted by model 4 (3-factor interaction model) based on ± 1 SD of the mean for each predictor: high and low restraint (±5) and high and low disinhibition (±4). Light bars represent low restrained eaters; dark bars represent highly restrained eaters. Weights were estimated by using multilevel modeling (SAS PROC MIXED; SAS Institute, Cary, NC).

FIGURE 2

Effect of dieting status, dietary restraint, and dietary disinhibition on weight change over time (n = 163). Weight values were predicted by model 4 (3-factor interaction model) based on ±1 SD of the mean for each predictor: high and low restraint (±5) and high and low disinhibition (±4). Solid lines represent low restrained eaters; dashed lines represent highly restrained eaters. Weights were estimated by using multilevel modeling (SAS PROC MIXED; SAS Institute, Cary, NC).